Asynchronous interface modules provide high-density terminal server functionality to Cisco® 4000 Series Integrated Services Routers (ISRs). Up to 200 terminal server connections can be supported on a single platform—eight more than are supported on the Cisco ISR G2.

Asynchronous interface modules are offered as both a Network Interface Module (NIM) and a high-density Service Module (SM) (Figure 1).

Table 1 lists the asynchronous NIM and SM SKUs.